Namespace not recognized (even though it is there)

Question

I am getting this error:

The type or namespace name \'AutoMapper\' could not be found (are you missing a using directive or an assembly reference?)

Answer 1

This question has already been answered for the original poster, but in case someone encounters this in an MS-Test project:

from within Visual Studio, click the Test menu -> Test Settings -> Default Processor Architecture and ensure that the architecture matches that of the other assembly that you're referencing. If the other assembly is x64 and your test settings are x86, you may experience the symptoms that the original poster had.